Free PLC troubleshooting guides
Understand the signal.
Then find the fault.
For new technicians, working maintenance teams, and people considering the trade. Start with a problem you can recognize, not a wall of unfamiliar terms.
The belt is clear.
Why does the photoeye say blocked?
Understand a blocked photoeye input on a clear conveyor. Compare the sensor, physical input, PLC tag, and ladder logic using PLCTrain simulation examples.
XIC vs XIO.
Read the bit, not the name.
Learn when XIC and XIO instructions are true, why green does not mean a sensor is healthy, and how a blocked photoeye affects a conveyor rung.
Run command: ON.
Conveyor: STOPPED.
Both can be true.
Understand the difference between a PLC run command, output command, and actual conveyor motion. Learn to explain why a requested start may not move a belt.
How to use these guides
Read. Predict.
Then try.
First, explain what a signal means in plain language. Next, predict what should happen. Then use the demo to compare your prediction with the conveyor and the ladder logic.
A correct guess is not the whole skill. Be able to explain which observation supports your diagnosis, what you changed, and how you proved the repair.
These guides and the preview are public. Playing the trial and saving your progress require a confirmed account.
For the person training a team
Ask for the evidence.
Have a learner describe the physical sensor, the input being read, the tag used in the rung, and the expected output. If those get mixed together, that is a useful coaching target.
The trial is a sample of the training approach, not a completed industrial-maintenance curriculum or a trade qualification. The manager report on the home page is an illustrative layout, not a live team dashboard.